Control system for airplanes



Nov. 25, 1941. T. N. JOYCE CONTROL SYSTEM FOR AIRPLANES Filed March 16,1939 4 Sheets-Sheet 1 Z] ruin/Mom 7277/71? Jam? NOV. 25, 1941. N JOYCECONTROL SYSTEM FOR AIRPLANES Filed March 16, 1939 4 Sheets-Sheet 2 Nov.25, 1941. T. N. JOYCE CONTROL SYSTEM FOR AIRPLANES 4 Sheets-Sheet 5Filed March 16,

Nov. 25, 1941. T. N. JOYCE 7 2,263,992

CONTROL SYSTEM FOR AIRPLANES Filed March is, 1939 4 Sheets-Sheet 4Patented Nov. 25, 1941 CONTROL SYSTEM FOR AIRPLANES Q Temple N. Joyce,Arnold, Md., assignor to Zap I Development Corporation, Baltimore, Md.,a

corporation of Delaware Application March 16, 1939, Serial No. 262,264

(01. 244-90) The present invention relates to airplanes and 8 Claims.

more particularly to a control system for airplanes. This invention isgenerally similar to that disclosed in my co-pending application, SerialNo. 220,359, flled July 20, 1938, but constitutes an improvementthereover.

It is of course well known that it is advisable to employ wings in whichthe ratio of maximum lift to minimum drag that can be obtained isrelatively large. At the present time wing flaps are being used toincrease that ratio of a wing by increasing the maximum lift obtainablewithout the necessity of increasingthe minimum drag any appreciableamount. Moreover, wings of variable camber and variable area are alsoresorted to in anvendeavor to securean increase in this ratio.

The constructions above set forth are not particularly desirable in viewof the fact that they are' somewhat complex in structural detail and thecost of manufacture of such constructions is so high as to render theiruse prohibitive. In addition, another undesirable factor is that theflaps conflict with the ailerons and thereby hinder the emciency ofeither or both of these control surfaces.

An object of the present invention is to provide means to increase theemciency of the lifting and lateral control surfaces of an airplane.

Another object of the present invention is to provide an airplane withproper lateral control at both high and low speeds.

Yet another object of the present invention is to provide-a flap andaileron combination which will permit the use of full-span 'fiaps.

And still a further object-of the present invention is to provide a winghaving spoiler, flap the present invention there is provided an arandaileron surfaces in which the aileron cannot be operated so long as theflap is in its nested or inoperative position.

Yet a further object of the present invention is to provide an aileronwhich is under positive control at all times.

A still further object ofthe present invention is to provide a winghaving an aileron that is adapted to be moved into the slip stream aboutthe wing which is provided with means to prevent fluttering of theaileron during its movement into and out of the slip stream.

And yet a still further object of the present in vention is to provide awing having an aileron that is adapted to be moved into the slip streamwith means which will prevent the aileron from operative position exceptwhen the aileron is in its neutral position.

To accomplish the above and other. important objects, my invention ingeneral embraces the idea of providing a wing with spoiler, flap andaileron surfaces that are suitably associated with each other. u

When the airplane is flying at high speeds the flap and aileron are intheir nested or inoperative positions, and it is impossible to move theaileron to its operative position so long as the flap is in itsinoperative position. However, at the same time the spoilers can beactuated by the pilot 'of the plane to give the necessary lateralcontrol to the ship. This arrangement is high- 1y desirable since (willprevent the ailerons beingripped off or otherwisedamaged or adverselyaffected by ice. v

On the other hand, however, when the ship is flying at low speeds andthe flap islowerd the aileron is moved into the slip stream and can'eflective at low speeds due to thefact that it lies in a stimulatedflow of air over .the top surface of the wing that is caused by thelowering of the flap. Therefore, any movement of the aileron surface hasan increased effect on the lateral movement .of the wing. In addition,in

rangement whereby the aileron is undervpositive control at all timesand'fiuttering of the aileronsis prevented during its extension into theslip stream or its retraction into its nest within the Wing- Moreover,the aileron cannot be retracted except when it is in its neutralposition.

In order to make my invention more clearly understood there is depictedin the accompanying drawings means for carrying the same into practicaleflect without limiting the improvements in their useful applications tothe particular constructions which, for the purpose of explanation, havebeen made the subject of illustration. I In the drawingsfin which likenumerals designate similar parts: .s

Figure 1 is a top plan view of an airplane embodying my invention. L

Figure 2 is a fragmental transverse sectional view of a wing showing theaileron and'flap in being moved from the slip streaminto its intheirextended or operative positions.

Figure 3 is a fragmental transverse sectional cation, Serial terminate'in proximity view showing the aileron and flap in their retracted ornested positions.

Figure 4 is a fragmental plan view illustrating the control mechanismfor the spoiler and aileron surfaces.

Figure 5 is a sectional view taken along the line 6-6 of Figure 4.-

Figure 6 is a sectional view taken along the line 6-6 of Figure 5looking in thedl-rection of the arrows showing the position of the partswhen the aileron surfaces are in connection with the pilot's controlcolumn.

Figure '7 is a sectional view similar to Figu e 6 showing the positionof the parts when the aileron control surfaces are disconnected from thepilots control column.

8-8 of Figure 6 looking arrows.

Figure 9 is a 8,-8 of Figure 7.

Referring to the drawings and more particuin the direction of the Figure8 is a sectional view taken along the line sectional view taken alongthe line larly to Figure 1, thereis illustrated an'airplane having a.fuselage l, power plant 2, empennage structure 8, and wings 4. I

A wing flap 6 of the. Zap type of suitable construction as describedin'my co-pending appli-' No. 220,359, is connected to the lower surfaceof the wings 4 by a double link mechanism to provide a downward andrearward movement of the flap. The flap moving means comprisesforwardlinks 6 pivotally attached at' their lower end to the flap as at I; andrigidly attached at their upper end to a torque tube 8 and adapted to berotated by suitable mechanism plctedv at 81. The lower ends of the armsare also universally connected to a push rod 38 as shown at 88. The pushrod 38 is suitably journaled in the internal structure of the wing andis adapted to move in roller bearings which I have designated 48. Thebearings 48 are carried by support members 4| that can be attached inany desirable manner to the internal wing structure. Due to the angularrelation of the links 35 umn l8, there is provided the followingmeshanism. A lever 58 pivoted at 5| to the fuselage structure comprisesfour right angularly disposed arms 62, 53', 54 and 55. The arm 52 hasattached thereto cables 56 which are in turn connected to the controlcolumn l3. To each of the arms 53 and 54, the rearward ends of the pushrods 22 are universally connected. The arm is bifurcated and adapted toactuate an aileron operating mechanism designated generally 51.

The mechanism 51 comprises a slide 58, to the opposite ends of which arepivotally attached theinner ends of the push rods 88. The slide 58 iscarried in rectangularly broached aperture 59 formed in a sleeve 68which'in turn is slidably under control of the pilot. Rear links 8 arepivotally secured tothe flap andmovably suspended at I l to a transversetorque tube l2 suitably journaled in the wing structure.

The wings 4 are provided with spoiler surfaces I5 that are adapted to bemoved through lateral slots 16 provided in the upper leading surfaces ofthe/wing 4. As shown in Figure 2, each spoiler carried by a guide block8|. The guide is rigidly attached to a suitable web-member 62 of thefuselage. Y

Slots 63 in the bifurcated end of the arm55 engage anti-frictiontrunnion pins 64 which are.

attached to the sleeve 68. The pins 64 are also adapted to ride in slots65 in the upper and lower faces of the guide block 6|. As shown inFigure 4,,rotary movement of the lever 58 .will impart l8 comprises asegment II that is provided at its 7 lower end with arms l8. The arms l8are at-' tached to a torque tube I! that is suitably supported withinthe inner structure of the wing. The upper end of a short arm 28 isaffixed to each linear movement to the sleeve 68.

' A pin 66 mounted to move transversely in the slide 58 is provided toalternately engage the slide 68 with either the sleeve 68 or the guideblock 6 I.

This is accomplished by the pin 66 either being torque tube l8 and thelower end is attached to a connection 2|. Each connection 2| isassociated with a push rod 22 whichextends longitudinally of thefuselage and is of such length as to to. a control mechanism foroperation ofthe spoilers and ailerons which may beoperated by-thecontrol'column ll of the plane which is located within the pilot'scompartment.

forced into an aperture 61 in the sleeve or' an aperture 68in the guide6|. A helical spring 68 is provided to normally force the pin into theaperture 68. y

As depicted in,Figure 6, when the pin 66 locks the slide 58 to thesleeve 68, movement of the sleeve caused by rotation of the lever 50will also As best'shown' in Figure 3. the upper trailing edge of ,eachwing 4 is formed with a depressed area or nest 26 in which an aileron 26is adapted to be positioned-when it is in its inoperative position.'Aileron supporting arms 21 are pivoted at their upper ends to theaileron 26 at 28, and the lower ends of the arms are attached to atorque tube l2 supported within thewing. A crank 28 is afllxed to thetorque tube and a piston'rod 88, that is moved bya cylinder II, ispivotally connected to the upper end of the crank; As will later be morefully discussed. the piston rod 88,

- crank 26, torque tube l2, and arm. 21 provide means-whereby theaileron nlay be moved from its nested to its operative position orretracted againtoitsnestedposition;

.Links 86 are universally connected to pins 86 carried by the leadingedge of the aileron as decause movement of slide 68 and the push rods 28to impart angular movement to the ailerons. At the same time, thespoilers l5 will also be operated through the rods 22. Referring toFigure 7, it will be seen that when the pin 66 locks the slide 58 to theguide 6|, movement will only be imparted to the sleeve 68, and thismovement of the sleeve relative to the slide 58 and the pin 66 iseffected by allowing the pin 66 to travel in a slot .in the rear face ofthe sleeve 68; thereby permitting only the spoilers to operate.

.-In order to -manipulate the locking pin 66,

there is provided a pivoted lever 18 located at a position convenient tothe pilot. This lever is formed with a notched segment II and detent"and has attached to one end thereof a flexible cable 18. The oppositeend of the cable I8 is 'fixed to a rod 14 slidably carried in a valvecasing 15, whichcasing is attached to the guide 88 as at 16 (see Figure8). A helical spring 18 surrounds the rod 14 and is adapted to forceimparted to the right and left force the pin 66 into the aperture 88.

- In order that the slide 58 may be engaged with or disengaged from thesleeve 50 only when the aileron is in proper position for extension orretraction. there is provided a plate 80 attached at 8| to the slide 58.This plate travels in a groove 82 formed in the guide 6| adjacent thevalve casing '75. An elongated aperture 83 is formed in the plate 80which is enlarged at 84. The enlarged portion 84 is so located that whenthe slide 58 is centrally positioned in the,

sleeve 55, it will be concentric-with the end of the rod 76. The rod 74is provided with an enlarged collar 85 that will only pass through theportion 89 of the slot 82, thus the rod only moves the locking pin 89when the slidev 58 is centrally located in thersleeve 80 or, in otherwords, when the aileron is in proper position for retraction (zero angleposition).

To manipulate the lever 70, regardless of the position of the lever 58,which controls the spoilers and the ailerons, a spring loaded lostmotion. connector 88 is disposed in the flexible cable 73. The spring 89of the connector overrides the spring 78 while the spring 78overbalances the spring 69.

To move the aileron 25 to its operative and inoperative positions, fluidunder pressure is admitted to the cylinder 3| through a line 99connectedt'o the valve casing 15. The casing 75 is provided with atransverse passage 98 adapted to register with a bore 92 in the rod 75.A line 93 connects with the inlet passage 99 of a piston valve'95. Th'episton valve 95 is in communication with the lines 96 and 97, whichlines respectively connect with opposite 'ends of the cylinder 3!. Thepiston 98 of the valve 95 is provided with a head 99 between which headand the valve casing is disposed a spring Hill to hold normally thevalve in the position shown in Figure 6. The. valve is adapted to bemoved into the position shown in Figure '7 by the leading trol. Thelever III is then moved to the position shown in Figure 6 allowing thespring 18 to force the-rod 74 into engagement with the pin "66 to lockthe slide 58 to the sleeve 60; As above set forth, when the slide 58 andthe sleeve 68 are connected, movement of the'lever 50 by means of thecontrol column l3 will impart difierential angular movement to theaileron. Obviously, when the airplane is under lateral control by meansof the ailerons, it is not necessary to disconnect the operating meansto the spoiler surfaces by reason of the fact that on the wing where heaileron is at a position angle of attack, the spoiler on thiswing ismoved out of the airstream over the wing. On the opposite wing, wherethe aileron is at a negativeangle of attack, the spoileris extended intothe airstream, but as the airstream over this wing is already spoiled bythe negative angle of the aileron, the spoiler will serve to produceadditional beneficial yaw to this wing.

When the pilot retracts the flaps to increase speed, the flap 5 againengages the head 99 of the valve 95 to move the same to its retractingposition as shown in Figure '7. The pilot then moves the lever '70 towithdraw the rod M and open the valve 75 for passage of fluid to theretracting cylinder. If the slide 58 is centrally located in the sleeve60, and the ailerons are in the zero angle position, the enlarged collar85 on the rod 74 will pass through the portion 88 of the slot 83 in theplate 89 and allow the parts to assume the position shown in Figure '7.However, should the ailerons be in other than zero angle position, thelever it may be moved to' place tension inthe connector 88. and when theailerons are moved to their zero angle position, the position of theparts shown in Figure '7 may be automatically assumed.

By the above construction, the ailerons may only be nested when they arein their zero angle position thereby permitting proper retraction andpreventing damage to the ailerons. This construction also assures thatthe ailerons will be edge ll of the flap 5 when the flap is in itsretracted position as illustrated in Figure 3.

The exhaust ports I02 of the valve 95 are I connected with a lin 103which returns the fluid to the source of supply.

In operation, consider the airplane flying at high speed under lateralcontrol by the spoilers l5. When under control of the spoilers. theoperating unit 51 and its associated parts will be in the position shownin-Figure '7, where the slide 58 is in locked engagement withguide Si bymeansof the pin 56. The valve 75 will be held inopen position by thelever '70 and the flexible cable 73, and the 'valve 95 will be held bythe flap 5 in position to admit fluid to the aileron retracting end ofthe cylinder 3|.

Should the pilotdesire to reduce the speed of the airplane so that thespoilers will no longer b efl'ective forlateral control, he lowers theflap. As the leading edge of the flap moves away from the valve head99;, the position of the valve piston 98 will change to admit fluidthrough the line 9i'to the aileron extending end of the cylinder,

3i, thus moving the aileron 26 to its'operative said spoiler and aileronsurfaces relative to said position, as the airplane is still underspoiler coiilocked in their zero angle position when bein extended andretracted.-

While I have shown and described the preferred embodiment of myinvention, I wish it to be understood that I do not confine myself tothe precise details of'construction herein set forth by way ofillustration, as it is apparent that .many changes and variations may bemade therein, by those skilled in the art, without departing from thespirit of the invention. or exceeding the scope of the appended claims.

I claim:

1. In an airplane assembly, a wing, spoiler,

flap and aileron surfaces for the wing adapted to be variably positionedwith respect thereto.

a single control operable for variably positioning wing and each other,said aileron normally restingin a recess in the wing and being adaptedto be bodily extended to an operative position above the upper surfaceof the wing and tiltable rela-' tive tothe latter by said singlecontrol, the flap andaileron being so connected that the aileron cannotbe extended unless the flap is lowered,

and means associated with the spoiler and ailer-' on control positivelyretaining the aileron against tilting in response to operation of saidcontrol while the aileron is being moved to its location above the wing.

2. In an airplane assembly, a wing,-spoiler,

flap andaileron surfaces for'the wing, a single the spoiler and aileronsurfaces, said I aileron normally resting in a recess formed in theupper trailing edge of the wing and being adapted to be bodily moved toa position above the trailing edgeof the wing to afiord lateral control,and means to so move the aileron surfaces, said flap and aileron beingso connected that the aileron cannot be extended unless the flap islowered, and'means associated with the spoiler and aileron control toretain the aileron against pivotal movement in response to operation ofsaid control member while the latter is being moved to its locationabove the wins.

3. In an airplane construction including a wing structure, pivotallymovable ailerons for said structure adapted to be bodily projectedthereabove to an operating position, and means for so projecting saidailerons, a control operably connectible with said ailerons and operableto eiIect pivotal movement thereof, and means re-.

taining said control against operable connection with said aileronsduring projection of the latter to said operating position.

4. In an airplane construction including a wing structure, pivotallymovable ailerons for said structureadapted to be bodily projectedthereabove to an operating position, and means for so projectingsaidailerons, means operable to efiect pivotal movement of saidailerons, and means rendering said means inoperative to efiect saidpivotal movement during projection of said ailerons to said operatingposition.

5. In an airplane construction, a wing structure, ailerons for saidstructure bodily movable to and from projected and retracted positions.respectively relative to said wing structure,

means for so moving said ailerons, means operable to control saidmovement'oi said ailerons, said ailerons having a normal position withrespect to said wing structure when in said projected position and beingtiltable therefrom, means operably connectible with said ailerons foreflecting tilting of the latter, and means operable in response tooperation of said control means for effecting said operating connectionwhen said ailerons are in said normal position only.

r control member operable tor pivotally moving 6. In an airplaneconstruction, a wing structure, ailerons for said structure bodilymovable from a nested position to an operating position with respectthereto, means for so moving said ailerons, said ailerons having anormal position with respect to said wing structure and being tiltabletherefrom, relatively movable parts adapted to be operably connected foreffecting said' tilting of said ailerons, and means accommodatingestablishment of said operable connection of said parts when saidailerons are in said normal position only.

'7. In an airplane construction, a wing structure, ailerons for saidstructure adapted to be bodily projected thereabove, means operable toeffect said projection, said ailerons having a normal position withrespect to said wing structure when projected and being tiltable fromsaid position to vary the angular relationship with respect thereto,deflector means at the leading edge of said wing structure adjustablewith respect thereto, common means operable to simultaneously effectadjustment of said deflector means and tilting of said ailerons fromsaid normal position, and means operable to render said common operatingmeans inoperative to efiect tilting of said ailerons when said aileronsare being projected.

8. In an airplane construction, a wing structure, ailerons for saidstructure adapted to be bodily projected thereabove, means operable toeflect said projection, said ailerons having a normal position withrespect to said wing structure when projected and being tiltable fromsaid position to vary the angular relationship with respect thereto,means movable to eflect tilting of said ailerons, deflector elementscarried at the leading edge of said wing structure and adjustable withrespect thereto, means operable to effect adjustment of said deflectorelements, and means operable to connect said last mentioned means withsaid movable means when said ailerons are in said normal position onlywhereby said deflector elements and said ailerons are simultaneouslyoperated.

- TEMPLE N. JOYCE.

